shield volcanoes

Shield volcanoes are broad, gently sloping volcanic mountains built by successive flows of fluid lava.

The shape resembles a warrior's shield lying face-up.

Unlike steep, explosive stratovolcanoes, shield volcanoes erupt relatively quietly, their runny basaltic lava spreading widely before cooling.

Mauna Loa and Mauna Kea in Hawaii are classic examples—measured from their base on the ocean floor, they rank among Earth's largest mountains.